tbi adapter advice

[Xenon]

So I'm finally ready to do the tbi conversion on my '87 Suburban. I had a thread about it on here long ago...

I'm looking for an adapter to go between my spreadbore manifold and the TBI... many to choose from. I was wondering if there is any one that is best? Or any I should avoid? It looks lie mostly the affordable ones are made by Trans Dapt but there are several styles...

Any input is appreciated. Thanks guys!



EDIT: Looking at this one maybe? It's a good price... Pros/Cons?

http://www.righttoolusa.com/p/Trans-...r-7822840.html

[gregs78cam]

Looks like that one is only 1/4" thick or so, I wouldn't go less 3/8", preferably 1/2" in aluminum. Steel you might get away with 1/4", as long as you have clearance for the threaded end of the bolt. I made my own so I can't comment on other's quality.

[EagleMark]

Haven't had much luck with Transdapt 1/4 inch metal plate adapters. Much better luck with 1/2 inch aluminum Holley adapters for a few dollars more.

The biggest issue with 1/4 plate adapters is not enough metal for TBI bolt threads. Look at the TransDapt adapter and draw a line from mounting bolts to intake. See the TBI bolts in the path? If they go though adapter by 1 thread it hits intake and pushes adapter up causing a vacuum leak.

Mount the TBI on adapter with gasket and tighen before putting the adapter on intake to check and see/trim bolts so they don't go through!

9QYB5qV7Zv.jpg

There's also a center mount.

trd-2211_w.jpg

[Xenon]

Thanks guys. Will look at the Holley adapters.

[jim_in_dorris]

Go to JY and pull a 454 TBI adaptor, It's a GM factory part. Spreadbore to TBI.

[Xenon]

How about this one? look ok?

http://www.summitracing.com/parts/HLY-17-41/

[EagleMark]

Go to JY and pull a 454 TBI adaptor, It's a GM factory part. Spreadbore to TBI.

I've got one of those big ugly things here on the bench I don't know what to do with...

How about this one? look ok?

http://www.summitracing.com/parts/HLY-17-41/

That's the one.